In general, a vehicle having an automatic transmission includes a shift range switching apparatus. A mechanical shift range switching apparatus has a structure, in which a shift range operating device such as a mechanical shift lever has a mechanical linkage with a shift range switching device. In this structure, a target shift range set using the shift range operating device steadily coincides with an actual shift range of the shift range switching device as long as the mechanical linkage does not cause a failure. However, the mechanical shift range switching apparatus may not be necessarily excellent in mountability, flexibility of designing, and the like.
According to JP-A-2002-323127, an electric shift range switching apparatus operates a shift range switching device of an automatic transmission by controlling an electric actuator. A driver switches the shift range via a shift range operating device such as a switch operated via a mechanical shift lever, a button for operating the shift range, and a joystick. In the electric shift range switching apparatus, a mechanical linkage between the shift range operating device and the shift range switching device is omitted, so that mountability of the shift range operating device and the shift range switching device can be enhanced. In addition, the structure of the electric shift range switching apparatus can be further freely and ergonomically designed to enhance controllability of the shift range operating device. Furthermore, a user can freely change the shift range operating device as appropriate.
In the electric shift range switching apparatus, the shift range operating device does not have the mechanical linkage with the shift range switching device. In this structure, the position of the electric actuator is supposed to be matching with the position of the shift range switching device. Accordingly, when the electric actuator actually does not match with the shift range switching device, the target shift range (recognized shift range) may not coincide with the actual shift range. When the target shift range (recognized shift range) does not coincide with the actual shift range, the vehicle may accidentally move by starting the engine even though the driver does not intend to move the vehicle. Therefore, the electric actuator needs to coincide with the shift range switching device to steadily restrict the vehicle from accidentally moving by starting the engine.
According to JP-A-2002-323127, a memory such as a non-volatile memory stores the actual shift range (previous shift range) when the engine is stopped. Subsequently, the previous shift range is recognized as the present actual shift range when the engine is started. However, the electrical actuator may be detached and attached for maintenance work or the like. The actual shift range may be changed while the electrical actuator is detached. In this condition, deviation may arise between the recognized shift range recognized by an electric actuator control device and the actual shift range. In this case, the vehicle may accidentally move by starting the engine even though the driver does not intend to move the vehicle.